2. Field of the Invention
The present invention relates to the field of pattern recognition. Specifically, the present invention relates to the field of systems for pattern recognition particularly useful for voice and handwriting recognition applications.
2. Prior Art
The ability to store and accurately recognize patterns is a particularly good application for general computer systems. Computer systems offer the unique ability to process at high speeds specialized procedures that are developed for the field of pattern recognition. Using pattern recognition technology, a computer system can be advantageously utilized to respond to variable patterns of information (such as handwritten characters and voice) rather than rigid input devices, such as a keyboard input device. Using such technology, a computer system can be utilized to recognize visible patterns, such as pictures and video frame, or audible patterns, such as voice and other sounds, or movement patterns such as handwriting. It would be advantageous, then, to provide a computer system with an efficient mechanism for pattern recognition for handwriting and voice input applications. The present invention offers such capability.
Typically, a library of reference or prototype patterns may be stored within the memory storage devices of a general purpose computer system implemented by software for pattern recognition. Each library pattern is further composed of many individual points or states that, in total, comprise the pattern representation. These known library reference patterns are then individually compared against an input pattern also composed of a multitude of points or states. The general purpose computer systems of the prior art are programmed to individually compare, point by point, or state by state, the individual components of a particular reference pattern to the individual components of the input unknown pattern. This continues for each reference pattern in the library of patterns. For each pattern a match path is developed that indicates the level of identity between the unknown and the reference patterns. Reference patterns with good match paths are then selected by the computer system as candidates for a resultant match. The computer system then analyzes each of the reported candidates to determine which is best matches the unknown input pattern. During a comparison, since the reference patterns are each compared against the unknown, they are constantly accessed by the computer system. Prior art pattern recognition systems store the reference patterns in a memory array that is coupled to the computer system bus. When a pattern recognition procedure is operating the constant access of these reference patterns over the host system bus tends to interfere with, if not eliminate, other tasks that the computer system may perform. Therefore, it would be advantageous to provide a pattern recognition system that eliminates this additional bus accessing to the reference patterns. The present invention allows such capability.
Heretofore, prior an systems for pattern recognition have typically been implemented using software techniques in general purpose computers. Although offering a good deal of flexibility, these general purpose computers do not offer the processing power and efficiency required to process the vast amount of data required for voice and/or handwriting recognition applications. In order to provide accurate and useful pattern recognition capabilities within a general purpose computer system, the reference library must contain a fair amount of reference patterns. Further, each reference pattern must contain a level of resolution to distinguish each individual known input. Moreover, since voice and handwriting samples may vary from person to person, each known reference pattern should contain a multitude of pattern variations. Each of the above limitations and requirements of a pattern recognition system require a great deal of computer processing capability. Prior an software systems simply to not offer enough processing power to allow a personal computer or desktop platform to realize accurate and useful handwriting and/or voice recognition applications. More processing power is needed to provide real-time accurate voice and/or handwriting recognition applications than the prior art can provide. Specifically, prior an computer systems that have pattern recognition procedures implemented primarily in software offer poor performance and do not readily provide rapid response time between an unknown pattern input and the resultant match output and are therefore not entirely user interactive.
General purpose computer systems offering pattern recognition capability are typically implemented within one of three levels of processing complexity. The first level of complexity (the lowest level) is programmed to recognize only patterns input according to a tight or ridged and predetermined format. For instance, these system recognize only handwritten letters if written within predetermined boxes on a predetermined format or voice input within predetermined timing windows. A second and higher level of complexity is system that can recognize a particular persons writing but does not require predetermined input boxes and may allow individual characters to touch or be cursive or natural. A third, and highest level of pattern recognition would recognize any written or spoken pattern that a person could otherwise recognize. As can be seen, each level of pattern recognition sophistication requires more processing power from the computer system. It would be advantageous to provide a system that could be used to interface with any of the systems as specified above to increase performance and accuracy of pattern recognition applications. The present invention offers such capability. Therefore, it would be advantageous to provide a system that could be interfaced with a general purpose computer, that would offer the power and efficiency for processing pattern recognition procedures while at the same offering the flexibility of a programmed general purpose computer system. It would further be advantageous to offer the above in a system specially optimized for voice and/or handwriting pattern recognition. The present invention offers such capabilities.
Accordingly, it is an object of the present invention to provide a pattern recognition system having the processing power and efficiency to realize real-time accurate pattern recognition procedures operating with general purpose computer systems. Further, it is an object of the present invention to provide such a pattern recognition system within a personal computer or desktop platform or pen-based computer system. It is an object of the present invention to provide a pattern recognition system having the capability to process high resolution patterns and provide enough accuracy to allow meaningful pattern recognition of voice and/or handwriting input patterns in real-time applications. Moreover, it is an object of the present invention to offer the capability of interfacing with any general purpose computer system to increase its overall pattern recognition power and efficiency as well as increasing accuracy of pattern recognition and performance. It is yet an object of the present invention to provide a pattern recognition system that interfaces with a general purpose computer system whereby the present invention reduces the pattern recognition processing load of a central processing unit of the general purpose computer system thus freeing the general purpose computer system for processing of other tasks or higher level pattern recognition software tasks. It is yet another object of the present invention to provide a method and mechanism to reduce bandwidth requirements over a computer system bus resulting in accessing of reference patterns to free up the computer bus for other information or communication tasks.